Manufacture of paper suitable for security-checks.



UNITED STATES A ENT oF IoE.

ROBERT CHARLES MENZIES AND JOHN EDINGTON AITKEN, F MUSSELBURG-H,

SCOTLAND.

MANUFACTURE OF PAPER SUITABLE FOR, SECURITY-CHECKS.

No Drawing.

To all whom it may concern:

Be it known that we, ROBERT CHARLES MENzIEs and JOHN EDINGTON AITKEN, both subjects of the King of the United Kingdom of Great Britain and Ireland, and residing at Musselburgh, Scotland, have invented a certain new and useful Improvement in the Manufacture of Paper Suitable for Security- Checks, of which the following is a specification.

This invention relates to improvements in the art of roducing paper suitable for security chec (S, stamps and other documents, by incorporating in the paper pulp in the process of manufacture of paper, or in1pre.g nating the partially or completely manufactured paper with, a compound of such nature that when the paper so treat-ed is written orprinted on with ordinary ink a reaction will take place as a result of which the color of the ink will be indelibly mordanted in the fibers of the paper.

According to the invent-ion, there is incorporated in the paper pulp, or the partially or completely manufactured paper is impregnated with, a soluble thiocyanate, preferably thiocyanate ofammonium, and a soluble salt of lead, desirably in such proportions that the insoluble thiocyanate of lead produced by the combination, will amount to 5 to per cent. of the'weight of the paper more or less; or there may be added directly to the pulp or paper thiocyanate of lead, desirably in the proportion of Specification of Letters Patent.

Application filed January 26, 1912.

Patented Feb. 10, 1914. Serial No. 673,697.

5 to 20 per cent. of the weight of the paper more or less.

Having now described our invention, what we claim and desire to secure by Letters Patent of the United States is 1. The herein described improvement in the manufacture of paper for security checks and other documents, which consists in subjecting the paper material to the action of a solution of a thiocyanate and of a solution of salt of lead and producing in the paper, by reaction, thiocyanate of lead.

. 2. The herein described in'iproveinent in the manufacture of paper for security checks and other documents, which consists in subjecting the paper material to the action of a solution of thiocyanate of ammonium and of a solution of a salt of lead, and producing in the paper, by reaction, thiocyanate of ead.

3. Paper loaded with thiocyanate of lead.

4. Paper loaded with thiocyanate of lead" in about the proportions of not less than 5% and not more than 20% of the weight of lhe paper.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

ROBERT oHARILEs MENZIES. JOHN EDINGTON AITKEN.

Witnesses:

WILLACE FAIRWEATHER, JOHN MCCLEARY. 

